冷却孔布置对透平转静腔室性能影响的数值研究
Numerical Investigation for Effect of Coolant Inlet Arrangements on Performance of Turbine Rotor-Stator Cavity

采用SST湍流模型数值研究了透平第二级转、静腔室的流动与封严特性,分析了冷却孔布置对腔室内的流动、冷却效率以及主流燃气入侵特性的影响。研究表明:冷却孔的位置对上游腔室内的流动影响较大,对下游腔室基本无影响;冷却孔距离上游越近,上游腔室的旋流比越大,级间密封进口的旋流比越小,密封进、出口压比越小,相应的流过级间密封的质量流量越小,上游轮缘密封的燃气入侵量越小,上游腔室转、静壁面的冷却效率就越大;下游轮缘密封出流的旋流比越小,相应的主流通道的流动损失越大,但冷却孔位置对下游腔室内的旋流比和壁面冷却效率的影响很小;随着冷却空气流量的增加,3种冷却孔布置下上游腔室壁面冷却效率的差值减小。
The flow and sealing performance of secondary rotor？？stator cavity was numerically investigated with SST turbulence model. The effect of coolant inlet position on cavity flow, cooling performance and mainstream ingestion phenomenon were analyzed. The results show that the influence of coolant inlet position on the flow in upstream cavity is significant, while that in downstream cavity is slight. As the coolant inlet position moves toward upstream, the swirl ratio in the upstream cavity increases, the swirl ratio at the inlet of interstage labyrinth seal decreases, the pressure ratio and mass flow through interstage labyrinth seal decrease, the mass flow of mainstream ingestion on the upstream rim seal decreases, and meanwhile the cooling performance of the upstream cavity walls increases; whilst the swirl ratio on the downstream rim seal decreases, correspondingly the flow losses of mainstream flow increase, while the swirl ratio and walls cooling performance in the downstream cavity slightly depends on the coolant inlet position. As the mass flow rate of cooling air increases, the difference in cooling performance of the upstream cavity walls set in different coolant inlet positions decreases